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contracts...Escrow.sol

pragma solidity >=0.7.0 <0.9.0;

contract Escrow {
    
    address agent; // nobody else can use this contract
    
    mapping(address => uint256) public deposits;
    
    modifier onlyAgent() {
        require(msg.sender == agent);
        _;
    }
    
    constructor() {
        agent = msg.sender; // whoever deployed this contract will be the agent
    }
    
    function deposit(address payee) public onlyAgent payable {
        uint256 amount = msg.value;
        deposits[payee] = deposits[payee] + amount; // TODO use SafeMath
    }
    
    function withdraw(address payable payee) public onlyAgent {
        uint256 payment = deposits[payee];
        deposits[payee] = 0;
        payee.transfer(payment);
    }
    
}